The Golden Phoenix. The Gods of Space and Time, #4

A fast-paced adventure in which a handful of intergalactic hotshots flex a lot more than alien muscle power in an effort to outwit a necromancer with delusions of grandeur. Addric's first visit to Planet Earth was supposed to be a holiday but it turns into a race against time to rescue his brother's girlfriend from a fate worse than death. Accompanied by a few feisty friends, they have to battle it out in the Roman arena, cross the Arctic Ocean on a crystal-powered boat, venture deep into the bowels of the Earth, and then brave the fires of hell on a volcanic planet on the verge of a major transformation.
It will take something more than sharp claws and attitude to save Elisabeth, and to defeat a necromancer at his own game, but these boys have a few tricks up their sleeve.